Socialite Paris Hilton is decked out in a heroine outfit as she leaves a Halloween party in Los Angeles

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Nick Lachey guest hosts “Live! with Regis and Kelly”with Kelly Ripa, and they dress up in two different costumes. Ripa dresses first as one of the “Toddlers in Tiaras,” and Lachey goes as Charlie Sheen.

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Ripa and Lachey then dress up as Kim Kardashian and Kris Humphries.

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“Today” co-anchors Matt Lauer and Ann Curry dress as Prince William and Kate Middleton on their wedding day.

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“Real Housewives of New Jersey” star Teresa Guidice attends a Halloween party at the Top of the Rock’s 620 Loft & Garden.

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Alessandra Ambrosio dresses up for Halloween as she takes her daughter trick-or-treating.

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Giada De Laurentiis dons a Katy Perry costume.

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“Boardwalk Empire” star Gretchen Mol, dressed as Raggedy Ann, goes to a Halloween party in the West Village with her family.

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Belle of the ball: Gwen Stefani is dressed up as a Princess for Halloween costume party at Beverly Wilshire Hotel in Los Angeles.

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Actress Debra Messing and hejr husband David Zelman get ghoulish for Bette Midler’s Hulaween event in New York City.

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Me-oww! Nicky Hilton dresses as a leopard for a Halloween party in Los Angeles.

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What a party animal! Nicole “Snooki” Polizzi shows her wild side while hosting at Pure night club inside the Caesars Hotel in Las Vegas.